tee shirt printing on Fabric and paper are handle differently when printing designs on them. Their individual properties affect the final output of the prints on them. Paper translates the output from the screen without affecting the sharpness of the colour. They are also not as absorbent as cloth and so the ink dries faster on them than in fabrics. It also requires less colour mixing. The ink dries quickly near the surface on paper. Fabric on the other hand is absorbent and allows the ink to penetrate deeper in it. It is thus a better option for permanent print. This property of cloth also affects the way colours look on them. A dark coloured t-shirt processed with a light coloured ink tends to hide behind the louder colour. For example, if a white print needs to be designed on a black t- shirt, then in such cases the black tends to dominate the white. This can be overcome by running the white ink two times with flashing between each run of the printer to etch the perfect design.
Flashing is a process used very commonly in printing on fabric which involves curing the ink temporarily with the help of a heat lamp. It is then again printed on the same screen. This strengthens the ink and prevents the colour of the shirt from pushing through it.It also does not hide the light print behind a dark background.
Another technique applied for printing light colours on dark fabrics is to use a white under base. Here all the designs are printed on white first which creates a blank canvas under the actual colour design. The under base procedure is very effective to get the colours in its original brightness on a dark coloured t- shirt. Either of these two techniques works well when t-shirt printing is done on dark coloured t-shirts.